EVEN though Nelly was still in mourning for his sister, who succumbed to leukemia two weeks ago, he put on a happy face and crafted one of the best rap shows to ever play the Garden.

Where most rap concerts cut production corners and come off as amateurish events, Nelly’s 3 1/2-hour show (that also had Fat Joe and T.I. on the bill) was slick, with good staging and top-shelf sound and video. Everyone from the lighting tech to the artists took the performance seriously.

Nelly and company kept the concert moving. Between acts there was never down-time, so the event never lost momentum and the sold-out house didn’t get restless.

This was the kind of performance that thrust Nelly into the vanguard of hip-pop and, in turn, pushed rap even closer to the front of American music.

How much closer?

At Friday’s show, Nelly boasted, “I’m the first rap artist who made the top 10 country charts.” He didn’t accomplish that when he was conjugating “Country Grammar” back in 2000, but rather on his recent duet with Nashville icon Tim McGraw on “Over and Over.” While the famous twanger didn’t make it to the Garden to lend Nelly a hand Friday, the tune was still a highlight.

That one and other material from last fall’s “Sweat” and “Suit” albums were the heart of the program, but where the St. Louis rapper found the most love from the house was when he did material from “Country Grammar” and “Nellyville.”

Nelly’s ode to sneakers, “Air Force Ones,” opened the show powerfully and immediately got the fans out of their seats dancing, but it was his mega-hit “Hot in Herre,” an unabashed request for nakedness, where he tucked the house into his vest pocket. Noticeably absent in the set was his controversial number “Pimp Juice.”

Nelly’s music is mostly about girls and the party that life can be. He knows that has been his strength in cracking pop and his weakness on the streets – he isn’t a cock-the-Glock thug.

T.I., who opened the show with material from his “Urban Legend” disc, was the night’s tough guy. His delivery was forceful yet smooth and had the kind of sonic clarity that said he wanted all his words understood.

Lil’ Jon made a curious cameo during T.I.’s set. He tried to join in on the fast-patter pieces, but was only able to participate when the chorus turned to simple chant lines like “Stand up.”

Hometown rapper Fat Joe, who had the middle slot on the bill, got a huge response when he worked his radio hit “Lean Back.” Joe is a fine performer and carried his weight at this concert with his unique staccato style, his New York attitude and his big-bone stage grace.

But, Joe, buy a belt or suspenders. It’s way too distracting having to watch you hitch up your britches 10 times a song.